/*
   Copyright (c) 2012 Mizar Tools Contributors (mizartools.org)

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/
/*  Contributors :
 *	2012-04-01 Marco Riccardi - initial implementation
 *
 */
package org.mizartools.system.xml;

import java.util.LinkedList;

import org.mizartools.system.ElementParseException;
import org.mizartools.system.IElement;
import org.mizartools.system.INode;
import org.mizartools.utility.xml.XMLElement;

public class Reducibility implements IElement {


    public static final String NAME = "Reducibility";

    private INode parentNode;

    private Proposition proposition = null;
    private Justification justification = null;

    private Reducibility(INode parentNode){
        this.parentNode = parentNode;
    }

    public INode getParentNode() {
        return parentNode;
    }

    public static Reducibility newInstance(INode parentNode, LinkedList<XMLElement> xmlElementList) throws ElementParseException {
        Reducibility reductionRegistration = new Reducibility(parentNode);
        XMLElement xmlElement = xmlElementList.poll();
        if (!xmlElement.getName().equals(NAME)){
            throw new ElementParseException(ElementParseException.NOT_VALID_ELEMENT, "XMLElement is a " + xmlElement.getName() + " not a " + NAME, xmlElementList);
        }

        if (!xmlElement.isEmpty()){
            while (true){
                xmlElement = xmlElementList.peek();
                if (xmlElement == null){
                    throw new ElementParseException(ElementParseException.UNEXPECTED_END_OF_FILE, "Unexpected end of XMLElement list");
                }
                if (xmlElement.getName().equals(NAME) && xmlElement.isEndElement()){
                    xmlElement = xmlElementList.poll();
                    break;
                }
                if (xmlElement.getName().equals("Proposition")){
                    if (reductionRegistration.proposition == null) {
                        reductionRegistration.proposition = Proposition.newInstance(reductionRegistration, xmlElementList);
                    } else { 
                        throw new ElementParseException(ElementParseException.DUPLICATE_ELEMENT, "XMLElement list contains a duplicated <Proposition> in element " + NAME, xmlElementList);
                    }
                } else if (Justification.isJustification(xmlElement.getName())){
                    if (reductionRegistration.justification == null) {
                        reductionRegistration.justification = Justification.newInstance(reductionRegistration, xmlElementList);
                    } else { 
                        throw new ElementParseException(ElementParseException.DUPLICATE_ELEMENT, "XMLElement list contains a duplicated <Justification> in element " + NAME, xmlElementList);
                    }
                } else 
                    throw new ElementParseException(ElementParseException.NOT_VALID_ELEMENT, "The XMLElement " + xmlElement.getName() + " is not valid in " + NAME, xmlElementList);
            }
        }

        return reductionRegistration;
    }

    public LinkedList<XMLElement> getXMLElementList() {
        LinkedList<XMLElement> xmlElementList = new LinkedList<XMLElement>();
        XMLElement xmlElement = new XMLElement(NAME);
        boolean isEmpty = !(proposition != null || justification != null);
        xmlElement.setEmpty(isEmpty);
        xmlElementList.add(xmlElement);
        if (this.proposition != null){
            xmlElementList.addAll(this.proposition.getXMLElementList());
        }
        if (this.justification != null){
            xmlElementList.addAll(this.justification.getXMLElementList());
        }

        if (!isEmpty) { 
            xmlElement = new XMLElement(NAME);
            xmlElement.setEndElement(true);
            xmlElementList.add(xmlElement);
        }
        return xmlElementList;
    }

    public Proposition getProposition(){
        return proposition;
    }

    public Justification getJustification(){
        return justification;
    }

	@Override
	public void accept(Visitor visitor) {
		if (visitor.visit(this)) {
		}
		visitor.endVisit(this);
	}

	@Override
	public String toString(){
		ToStringVisitor toStringVisitor = new ToStringVisitor();
		this.accept(toStringVisitor);
		return toStringVisitor.toString();
	}

}
